//https://leetcode.cn/problems/path-with-maximum-gold/

class Solution {
    int dx[4] = { 0,0,1,-1 };
    int dy[4] = { 1,-1,0,0 };
    bool vist[16][16];
    int m, n;
    int ret;
public:
    int getMaximumGold(vector<vector<int>>& grid)
    {
        m = grid.size();
        n = grid[0].size();
        for (int i = 0; i < m; i++)
        {
            for (int j = 0; j < n; j++)
            {
                if (grid[i][j])
                {
                    vist[i][j] = true;
                    dfs(grid, i, j, grid[i][j]);
                    vist[i][j] = false;
                }
            }
        }

        return ret;

    }

    void dfs(vector<vector<int>>& grid, int i, int j, int path)
    {
        ret = max(ret, path);

        for (int k = 0; k < 4; k++)
        {
            int x = i + dx[k];
            int y = j + dy[k];
            if (x >= 0 && x < m && y >= 0 && y < n && !vist[x][y] && grid[x][y])
            {
                vist[x][y] = true;
                dfs(grid, x, y, path + grid[x][y]);
                vist[x][y] = false;
            }
        }

    }
};